Import necessary modules

from pathlib import Path

from ipyniivue import download_dataset

DATA_FOLDER = Path("images")

download_dataset(
    "https://niivue.com/demos/images/",
    dest_folder=DATA_FOLDER,
    files=[
        "mean_func.nii.gz",
        "cope1.nii.gz",
        "tstat1.nii.gz",
    ],
)

Downloading mean_func.nii.gz...

Downloading cope1.nii.gz...

Downloading tstat1.nii.gz...
Dataset downloaded successfully to images.

import ipywidgets as widgets
from IPython.display import display

from ipyniivue import NiiVue

# Create NiiVue instance
nv = NiiVue(
    back_color=(0.2, 0.2, 0.3, 1),
)

volume_list = [
    {
        "path": DATA_FOLDER / "mean_func.nii.gz",
        "opacity": 1,
        "colormap": "gray",
    },
    {
        "path": DATA_FOLDER / "cope1.nii.gz",
        "colormap": "winter",
        "opacity": 0,
        "cal_min": 0.0,
        "cal_max": 100,
    },
    {
        "path": DATA_FOLDER / "tstat1.nii.gz",
        "opacity": 1,
        "colormap": "warm",
        "cal_min": 0,
        "cal_max": 4.5,
    },
]

nv.load_volumes(volume_list)

nv.overlay_outline_width = 0.25
nv.volumes[0].colorbar_visible = False
nv.opts.is_colorbar = True
nv.set_interpolation(True)
nv.scene.crosshair_pos = (0.55, 0.5, 0.8)
nv.opts.slice_type = "MULTIPLANAR"

# Setup dropdowns, sliders, and checkboxes

display_mode_dropdown = widgets.Dropdown(
    options=[("func", 0), ("cope", 1), ("tstat", 2), ("modulate", 3)],
    value=3,  # default is 'modulate'
    description="Display:",
)

tmax_slider = widgets.IntSlider(
    min=1,
    max=50,
    value=45,
    description="tMax",
)

cmax_slider = widgets.IntSlider(
    min=1,
    max=200,
    value=100,
    description="cMax",
)

outline_slider = widgets.FloatSlider(
    min=0,
    max=4,
    value=1,
    description="Outline",
)

clipdark_checkbox = widgets.Checkbox(
    value=False,
    description="ClipDark",
)

modulate_alpha_checkbox = widgets.Checkbox(
    value=True,
    description="ModulateAlpha",
)

# Setup callback functions


def on_tmax_slider_change(change):
    """Set tmax."""
    nv.volumes[2].cal_max = 0.1 * change["new"]


tmax_slider.observe(on_tmax_slider_change, names="value")


def on_cmax_slider_change(change):
    """Set cmax."""
    nv.volumes[1].cal_max = change["new"]


cmax_slider.observe(on_cmax_slider_change, names="value")


def on_outline_slider_change(change):
    """Set overlay outline width."""
    nv.overlay_outline_width = 0.25 * change["new"]


outline_slider.observe(on_outline_slider_change, names="value")


def on_clipdark_checkbox_change(change):
    """Set alpha clip dark."""
    nv.opts.is_alpha_clip_dark = change["new"]


clipdark_checkbox.observe(on_clipdark_checkbox_change, names="value")


def on_modulate_alpha_checkbox_change(change):
    """Modulate alpha."""
    on_display_mode_change({"new": display_mode_dropdown.value})


modulate_alpha_checkbox.observe(on_modulate_alpha_checkbox_change, names="value")


def on_display_mode_change(change):
    """Handle display mode change."""
    mode = change["new"]
    nv.set_opacity(0, 1.0)  # background opaque
    nv.set_opacity(1, 0.0)  # hide cope
    nv.set_opacity(2, 0.0)  # hide tstat
    idx = min(2, mode)
    nv.set_opacity(idx, 1.0)

    if mode == 3:  # modulate
        nv.set_opacity(1, 1.0)  # show cope
        nv.set_opacity(2, 0.0)  # hide tstat
        modulate_alpha = modulate_alpha_checkbox.value
        nv.set_modulation_image(
            nv.volumes[1].id,  # modulate this volume (cope)
            nv.volumes[2].id,  # with this volume (tstat)
            modulate_alpha,
        )
    else:
        nv.set_modulation_image(nv.volumes[1].id, "")


display_mode_dropdown.observe(on_display_mode_change, names="value")

# On volumes loaded/ready actions


@nv.on_image_loaded
def set_initial_display(volume):
    """Set initial display mode."""
    if all(v.id for v in nv.volumes):
        on_display_mode_change({"new": display_mode_dropdown.value})
        nv.on_image_loaded(set_initial_display, remove=True)  # remove after 1st run


# Handle location changes

location_output = widgets.HTML(value=" ")


@nv.on_location_change
def handle_location_change(location):
    """Handle location changes."""
    location_output.value = "  " + location["string"]


# Display all

controls = widgets.VBox(
    [
        display_mode_dropdown,
        tmax_slider,
        cmax_slider,
        outline_slider,
        clipdark_checkbox,
        modulate_alpha_checkbox,
    ]
)

display(widgets.VBox([controls, nv, location_output]))

nv.scene.scene_data

{'gamma': 1.0,
 'azimuth': 110.0,
 'elevation': 10.0,
 'crosshair_pos': [0.55, 0.5, 0.8],
 'clip_planes': [[0.0, 0.0, 0.0, 0.0]],
 'clip_plane_depth_azi_elevs': [[2.0, 0.0, 0.0]],
 'vol_scale_multiplier': 1.0,
 'pan2d_xyzmm': [0.0, 0.0, 0.0, 1.0]}